a?f a2f əx² ' ay² a²f a2f, a²f + + and ax2 T ay2' əz² + = 0 = 0 Respectively in the plane and in the three-dimensional space, they are known as equations of Laplace, which are satisfied by the temperature distributions in steady states T (x, y) and T (x, y, z), by the gravitational and electrostatic potentials. Show which Laplace equation the function below satisfies x, (d) f(х, у) 3D tg 1